You may have seem it already on Environment Canada; those temperatures will be warming quite a bit!
Coming up late this week, on the weekend, and also for a big chunk of next week temperatures are expected to be slightly to far above average. Currently, Environment Canada is forecasting a highest temperature for the heat wave of 17 degrees, AccuWeather is saying 16, and The Weather Network 13. I would say we’re probably going to get to somewhere between 15 and 20 degrees. For more details, you can check Element in a little while; I’m going to post a chart there soon.
There is something special about this heat wave – It’s actually our first “summer” heat wave. What’s a “summer” heat wave? Well, here’s an explanation:
In winter, heat waves are almost always caused by low pressure systems. Meanwhile, cold waves are created by high pressure systems. In summer it’s the opposite; heat is caused by a high, and cold is caused by a low. In spring and fall, it can be either, but usually the former half will have a similar pattern to the preceding season, and the latter half will have a similar pattern to the proceeding season.
So far, this spring we have not had any summer-like patterns, but this upcoming heat wave is going to change that, making it so that we will have had one yet. That’s a lot of one-syllable words in a row!
“But Ben, what’s causing this? Like really, what IS causing this?!” -You; March 2025
Currently, we have a rex block (a high north of a low that stretches the jet stream into a backward S shape) in the Pacific. The high is over the Aleutian islands, and the low is around the very outmost Hawai’ian Islands. As we look into the next 24 hours, we actually see the high fizzle out right away. Usually this would mean the upper-level ridge just fades to nothing. However the low has different plans. It harnesses the jet stream over Tuesday night before then actually reinforcing the upper-level ridge. As this point there is also high pressure off the west coast of the US, and a low in the southern US. This is starting to look like an omega block!
As the jet stream violently squeezes the off-the-west-coast high, a new one enters the scene. A new high that very quickly formed and strengthened over Yukon and the Northwest Territories is beginning to race down to the Canadian and even American prairies, and is pushing down the cold air, leaving average in its wake. This average is what we’re going to feel on Friday. Then, the low follows behind. However, the low is actually still in the Gulf of Alaska. What has happened is the low has created a very long trough which wraps all the way around the mountains, and down into Alberta, as it follows the high. The trough reaches Alberta on Saturday, and then we delve into the realm of above average temperatures.
How long will it last? Well, it seems maybe around next Tuesday a low will break up the omega block, so we might return to average around then. This is not completely guaranteed, but later next week the low might restrengthen and might seed another omega block and another high might reinforce that, but I’m really unsure.